I might have traced back some info on it:
This forum talks of Healing track bikes and one user mentions the underside of his BB is marked G.R. 23 and England, with serial number marked upside down on the seat clamp.
From there I searched for images of Healing track frames and stumbled into this picture, which would match the headtube style. The lugs are different, but hey, this one is from the 1940's...
So my guess is that it's a Healing track bike as it indicates
Importing bicycle parts Healing was quickly gaining a reputation for his quality and service among the cycling community[...]
Which would fit with the BB shell marked as made in England. The decals are definitely just fakery after a repaint.